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The quills of the African crested porcupine
(Hystrix Cristata)
It is the largest porcupine in the world. The black and white quills along the head and back of this spiny mammal can be raised in to a crest,hence it’s common name of crested porcupine,
These sturdy,sharp quills, which are about 35 centimeters long and marked with alternating light and dark bands, provide highly effective protection against predators.

Despite their spiky appearance,
Quills are simply specialized hairs composed of keratin, the same protein your finger nails are composed of.
A porcupine can have up to 30,000 quills on its back.
And contrary to popular believe,
Porcupines can not shoot their quills. But they do detach easily,if a predator were to attack a porcupine, the slightest touch can lodge dozens of quills in the predators body.
Luckily for the porcupine the quills do indeed grow back.